The State Department is sending Imam Feisal Abdul Rauf - the mastermind of the Ground Zero Mosque - on a trip through the Middle East to foster "greater understanding" about Islam and Muslim communities in the United States. However, important questions are being raised about whether this is simply a taxpayer-funded fundraising jaunt to underwrite his reviled project, which is moving ahead in Lower Manhattan.

Mr. Rauf is scheduled to go to Saudi Arabia, Dubai, Abu Dhabi, Bahrain and Qatar, the usual stops for Gulf-based fundraising. The State Department defends the five-country tour saying that Mr. Rauf is "a distinguished Muslim cleric," but surely the government could find another such figure in the United States who is not seeking millions of dollars to fund a construction project that has so strongly divided America.

By funding the trip so soon after New York City's Landmarks Preservation Commission gave the go-ahead to demolish the building on the proposed mosque site, the State Department is creating the appearance that the U.S. government is facilitating the construction of this shameful structure. It gives Mr. Rauf not only access but imprimatur to gather up foreign cash. And because Mr. Rauf has refused to reveal how he plans to finance his costly venture, the American public is left with the impression it will be a wholly foreign enterprise. This contradicts the argument that a mosque is needed in that part of New York City to provide services for a burgeoning Muslim population. If so many people need the mosque so badly, presumably they could figure out a way to pay for it themselves.

Americans also may be surprised to learn that the United States has been an active participant in mosque construction projects overseas. In April, U.S. Ambassador to Tanzania Alfonso E. Lenhardt helped cut the ribbon at the 12th-century Kizimkazi Mosque, which was refurbished with assistance from the United States under a program to preserve culturally significant buildings. The U.S. government also helped save the Amr Ebn El Aas Mosque in Cairo, which dates back to 642. The mosque's namesake was the Muslim conqueror of Christian Egypt, who built the structure on the site where he had pitched his tent before doing battle with the country's Byzantine rulers. For those who think the Ground Zero Mosque is an example of "Muslim triumphalism" glorifying conquest, the Amr Ebn El Aas Mosque is an example of such a monument - and one paid for with U.S. taxpayer funds.

The mosques being rebuilt by the United States are used for religious worship, which raises important First Amendment questions. U.S. taxpayer money should not be used to preserve and promote Islam, even abroad. In July 2009, the Office of the Inspector General published an audit of U.S. Agency for International Development (USAID) faith-based and community initiatives that examined whether government funds were being used for religious activities. The auditors found that while USAID was funding some religious activities, officials were "uncertain of whether such uses of Agency funding violate Agency regulations or the Establishment Clause of the First Amendment to the Constitution" when balanced against foreign-policy objectives.

For example, our government rebuilt the Al Shuhada Mosque in Fallujah, Iraq, expecting such benefits as "stimulating the economy, enhancing a sense of pride in the community, reducing opposition to international relief organizations operating in Fallujah, and reducing incentives among young men to participate in violence or insurgent groups." But Section 205.1(d) of title 22 of the Code of Federal Regulations prohibits USAID funds from being used for the rehabilitation of structures to the extent that those structures are used for "inherently religious activities." It is impossible to separate religion from a mosque; any such projects will necessarily support Islam.

The State Department is either wittingly or unwittingly using tax money to support Mr. Rauf's efforts to realize his dream of a supersized mosque blocks away from the sacred ground of the former World Trade Center, which was destroyed by Islamic fanaticism. This ill-considered decision will raise the ire of millions of Americans and illustrates the limits of what the denizens of Foggy Bottom know about diplomacy.